from rest_framework import serializers
from goods.models import SKU


class CartSerializer(serializers.Serializer):
    """
    购物车数据序列化器
    """
    sku_id = serializers.IntegerField(label='sku id ', min_value=1)
    count = serializers.IntegerField(label='数量', min_value=1)
    selected = serializers.BooleanField(label='是否勾选', default=True)

    def validate(self, data):
        try:
            sku = SKU.objects.get(id=data['sku_id'])
        except SKU.DoesNotExist:
            raise serializers.ValidationError('商品不存在')

        if data['count'] > sku.stock:
            raise serializers.ValidationError('商品库存不足')

        return data


class CartSKUSerializer(serializers.ModelSerializer):
    """购物车商品数据序列化器"""

    count = serializers.IntegerField(label="数量")
    selected = serializers.BooleanField(label="是否勾选")

    class Meta:
        model = SKU
        fields = ("id", "count", "name", "default_image_url", "price", "selected")


class CartDeleteSerializer(serializers.Serializer):
    """删除购物车数据序列化器"""

    sku_id = serializers.IntegerField(label="商品id", min_value=1)

    def validate_sku_id(self, value):
        try:
            sku = SKU.objects.get(id=value)
        except SKU.DoesNotExist:
            raise serializers.ValidationError("商品不存在")

        return value


class CartSelectedAllSerializer(serializers.Serializer):
    """购物车全选"""
    selected = serializers.BooleanField(label="全选")
